Reference cards explained: subject looks, text effects, backgrounds and hooks

A card is not a filter. It is an example the model follows for one part of the picture, which is why the right card sharpens a cover and the wrong one argues with it.

By the Thumbnail Bench team Published 13 min read
A matrix of the four reference card categories against what each changes in a render, example cards, and what to watch for.
On this page
  1. What a reference does to a render
  2. Subject looks: eleven ways to treat the person or object
  3. Text effects: fourteen ways to build the letters
  4. Backgrounds: thirteen settings
  5. Hooks: fourteen devices, one at most
  6. When a card helps and when it fights the scene
  7. Combinations that hold together
  8. A short procedure for choosing cards
  9. What to do next

A reference card is a small reference image you attach to a render so the model follows a specific look for one part of the picture: how the subject is treated, how the headline letters are built, what sits behind the subject, or which device points at the point. On Thumbnail Bench the reference library holds 52 cards in four categories (subject looks, text effects, backgrounds and hooks), they cost no credits, and a render takes at most one card per category. A card is not a filter. It shapes what gets painted, which is why the right one sharpens a cover and the wrong one argues with the scene you described.

What a reference does to a render

A prompt tells the model what to paint in words. A card shows it an example of how one part of a finished cover should look. The model treats the card as evidence about the result, alongside your words, and paints a picture that fits both. That is why the library's own description says the card preview is rough and the real thing is painted by the model: a card is not laid on top of the image afterwards, it shapes what gets painted in the first place, so the render is still your scene.

That has consequences, and they explain most of what happens when a card goes wrong.

A card and a prompt that disagree get averaged. If the prompt says "soft daylight in a plain kitchen" and the background card says Speed Lines, the model has two instructions about the same region and resolves them by compromise. The compromise is usually a muddy version of both, which is one of the routes to the generic look that the guide to how generators work and fail describes.

A card fills in what the prompt left out. If the prompt says nothing about the background and you add Dark Studio, the card does the setting's job cleanly. Cards are strongest where they are the only instruction for that region.

One card per category is a constraint that protects you. Two text effects on one headline or two backgrounds in one frame are contradictions by definition. The limit forces the choice that the design would need anyway.

Observed pattern

In our own use the effect of a card is strongest on text effects, because letters have few degrees of freedom and the model follows the example closely. It is broadest on backgrounds, where a card replaces the whole setting sentence of a prompt. It is subtlest on subject looks, which nudge how the person or object is treated but leave the pose and the expression to the prompt and the saved face.

Two mock thumbnails: on the left a calm face with the words EASY FIX on a hot orange field, on the right the same face and words on a cool pale field.
Same face, same headline. The finish on the left promises drama the calm face does not deliver; the finish on the right agrees with it.

Subject looks: eleven ways to treat the person or object

A subject look decides how the main element sits in the picture. It does not decide who the subject is; when the subject is a face, that comes from a saved face of a person who agreed to be on your thumbnails.

CardWhat it does to the renderUse it whenIt fights with
3D Pop-OutThe subject appears to break out of the frame with depth and edgeA big face or a product that should dominateEpic Scene, which wants the subject small
Speed BlurMotion streaks trail the subjectChallenges, gaming, fitness, anything in motionStudio Portrait calm, Bokeh stillness
Neon OutlineA glowing edge separates the subject from a dark groundGaming and tech on black backgroundsLight backgrounds, Light Burst
Extreme Close-UpThe face fills most of the frameThe Big Face layout, verdicts, confessionsEpic Scene; needs the prompt to reserve space for words
Studio PortraitSoft key light, clean skin, composedFinance, business, education, interviewsSpeed Lines, Neon Glitch text
Sticker Cut-OutA hard white border around the cut-out subjectCommentary, versus, comparisons, collage layoutsBokeh and other soft, photographic grounds
Before and AfterThe frame splits, the same person dull on the left and bright on the rightTransformations, fixes, glow-ups, any then-and-now storyEpic Scene and any card that wants one whole scene
Face-OffTwo people in profile stare each other down, red on one, blue on the otherDebates, versus, rivalries with two real peopleExtreme Close-Up; it needs both faces mid-size
Tiny vs GiantThe person is small in a corner under a giant version of the objectScale stories, "this thing is huge", unboxings of big thingsAny face-size rule; the face is small on purpose
Side ReactionA shoulders-up cut-out at one edge reacting to the rest of the frameCommentary, reaction covers, screenshots with a face beside them3D Pop-Out and Extreme Close-Up, which want the face central
Holding It UpThe person holds the object beside their face and looks at the cameraReviews, product tests, "I bought this"Speed Blur; the object must stay sharp

Extreme Close-Up and the Big Face layout are the same idea from two directions: the style sets the composition, the card pushes the framing tighter still. Use the card when the render keeps coming back with the face too small.

Text effects: fourteen ways to build the letters

A text effect is the category people search for, and it is the one to use most carefully, because it is painted by the model. That means it inherits the spelling caveat: an effect makes the letters more elaborate, and elaborate letters give the model more ways to get a shape wrong. Why generators misspell and the workflow that fixes it applies in full; the short rule is that an effect goes on the one or two big common words in the headline field, and anything that must be exact goes on a text layer in the editor, with no effect at all.

CardWhat the letters look likeWhat it signalsLegibility at thumb size
Fat 3DThick extruded block letters with a hard shadowLoud, confident, general purposeAmong the best; the shadow gives the edge
FireLetters burning at the top edgeDanger, heat, anger, a rantGlow softens the top of every letter
GoldPolished metallic gold lettersMoney, luxury, a winNeeds a dark ground; reads as texture on light
Gradient BevelTwo-tone letters with a bevelled edgePolished, gaming, techGood; the bevel adds an edge without glow
IceFrosted pale letters with a cold glowCold, calm, winter, a chillGood on dark or blue; disappears on white
Neon GlitchTube-light letters with digital distortionEnergy, tech, night, gamingDistortion eats thin strokes; keep words short
Sticker OutlineFlat letters with a thick contrasting borderCommentary, comedy, comparisonsBest of the set; a border survives anything
ChromeMirror-finish silver lettersCars, tech, hard surfacesNeeds a dark ground; a bright reflection can blank a letter
Marker PenHand-written red marker strokes, slightly unevenPersonal, urgent, a note scrawled on the pictureGood on plain grounds; thin strokes vanish on busy scenes
Boxed LabelWhite capitals inside a solid red boxNews, exposés, a caption or labelBest of the set with Sticker Outline; the box is its own contrast
Rubber StampRed inked stamp in a tilted borderVerdicts, "denied", "approved", official toneRough ink thins the strokes; keep to one short word
Frosted GlassTranslucent pale letters with a soft glowPremium, tech, calmLow contrast on light or white grounds
GraffitiSpray-painted pink and green letters with dripsStreet, music, youth culture, bold energyBusy by nature; needs a plain dark ground
Comic PopChunky yellow letters in a jagged white burstComedy, reactions, cartoons, a shoutThe burst is a big shape; leave room for the face
Thumbnail Bench recommends

Match the effect to the emotion on the face and the temperature of the scene. Fire text over a Sad face, Ice over an Excited one, Gold on a warning: each is a small contradiction that the viewer feels before reading. When in doubt, Fat 3D or Sticker Outline: they carry any emotion and read at any size, which is the same reason the fonts that survive feed size are heavy and plain.

On finance and education covers we would leave the text effect empty, even though Gold is the obvious card for a money story and a plain headline looks underdressed next to the row, because a plain white word beside a doubtful face reads as a verdict and a gold one reads as a pitch.

Backgrounds: thirteen settings

A background card replaces the setting part of your prompt, so use one or the other for the same region, not both. What a background is for and the four kinds that work is the design argument; here is how each card behaves.

CardWhat it puts behind the subjectFitsWatch for
Light BurstRays radiating from behind the subjectReveals, wins, energyWashes out a pale face; adds a second light source to the scene
BokehSoft out-of-focus lightsInterviews, finance, night vlogs, premium feelLow contrast against a dark subject; pair with a rim-lit face
Split ContrastTwo halves in opposing coloursVersus, before and after, this or thatWords crossing the seam; keep the headline on one half
Epic SceneA wide dramatic environmentTravel, story, scaleThe face shrinks; the prompt must insist on face size
Poor vs RichA money contrast across the frameFinance, lifestyle, money storiesClose to a cliché; watch for sameness in the row
Speed LinesComic radial motion linesGaming, challenges, fitnessReads as noise behind a calm face
Dark StudioBlack with a rim of light on the subjectAny face that needs separationThe safe default; also the most common look in some niches
Flat YellowA plain bright yellow fieldSticker Cut-Out faces, comedy, tutorials, anything that must pop in a dark feedYellow text disappears; use dark or white letters
Clean WhiteSeamless white with a floor shadowProduct shots, reviews, minimal educationPale faces and white text both lose their edge
Money RainBanknotes falling through the airMoney stories, wins, giveawaysDoubles up with Cash Burst; use one
Tech GridDark blue with a glowing grid and floating codeTech, coding, AI, gamingCyan text vanishes; the grid competes with Neon Outline
Red AlertDark crimson with a red glow and smokeWarnings, danger, a rant, "it's over"Fire text adds a second red; the whole frame goes one colour
Sunset SkyWarm orange to purple sky with cloudsTravel, vlogs, lifestyle, calm storiesWarm letters sink into it; use white or cool text

Split Contrast with a divider is the finish for the split-screen and versus layout; Epic Scene is the one card that deliberately breaks the face-size rule, which is only right when scale is the promise.

Hooks: fourteen devices, one at most

A hook is a device: a badge, an arrow, a circle, a burst. It directs, isolates or labels. It is also a fourth element, which is why the case against arrows and circles as a patch matters here. When a hook goes in, something else should come out, and the hook should never be the fix for an eye path the layout failed to build.

CardWhat it addsEarns its place when
Cash BurstBanknotes bursting into frameMoney is the stakes and no other object shows it
Red ArrowA single red arrowTwo things must be connected and the gaze cannot do it
Red CircleA red ring around one detailThe detail is small and the video is about that detail
Shadow FigureA dark unidentified silhouetteSomeone unnamed is the subject and you have no consent for a face
VS BadgeA versus badge at the seamTwo sides are being compared
Warning TapeHazard tape across part of the frameA warning or exposé the video actually delivers
TimerA red digital clock reading 00:59The video really is a race against time
TrophyA gold cup with confettiA win, a rank, a competition result
PadlockA closed gold padlockA secret, a locked feature, a paywall, a hack
Check vs XA green check beside a red XA right-or-wrong, do-or-don't comparison
Phone ScreenA tilted phone with a blank bright screenAn app, a text, something seen on a phone
ExplosionA fireball with smoke and sparksDestruction, a blow-up, a dramatic fail
Question MarkA glossy red 3D question markA mystery the video answers; use once, not on every cover
Shock EmojiA giant yellow shocked faceReaction covers when there is no real face to show

Shadow Figure deserves a note. It is the honest way to put "a person" on a cover when the person is not yours to show: a mystery buyer, an anonymous source, a scammer in a story. It carries the presence of a face without the likeness of one, and it needs no consent because it is no one.

When a card helps and when it fights the scene

Five checks catch nearly every bad combination before it costs a credit.

  1. Emotion. Does the effect or background agree with the face? A hot finish on a calm face, or a cold one on a scream, is a contradiction the viewer reads first.
  2. Light sources. Count them. Light Burst plus Fire text plus Neon Outline is three glows and no shadow, which is the flat, oversaturated look the model produces on its own.
  3. Motion. Speed Blur, Speed Lines and Neon Glitch say movement; Studio Portrait, Bokeh and Dark Studio say stillness. Pick a side.
  4. Scale. Epic Scene wants the subject small; Extreme Close-Up and 3D Pop-Out want it large. They cannot both be right.
  5. Niche fit. Poor vs Rich outside a money story, Warning Tape on a tutorial, Neon Glitch text on a Clean Edu lesson: each reads as the wrong genre, which is the expectation-fit failure in the design principles guide.
Observed pattern

The most common combination we see fail is not two cards fighting each other but a card fighting the prompt: a detailed setting sentence and a background card for a different setting. The render lands halfway between a kitchen and a studio, and the creator blames the model. Delete the setting sentence or drop the card.

Say you describe a kitchen: a burnt loaf on a wooden board, daylight from a window, your face behind it in a wince, and "I RUINED IT" in the headline field. Then you add Fire as the text effect and Light Burst as the background. The render comes back with flaming orange letters, rays behind your head, and a kitchen gone amber to make room for both, and the viewer infers a rant, or a house fire, from a face that is only embarrassed. Two glows, no daylight, one contradiction. Drop Light Burst, keep the window sentence, and swap Fire for Sticker Outline in white with a black border, so the burnt loaf is the darkest thing on the cover and the wince is the only drama.

Combinations that hold together

Each row is a finish for a layout, not a template. The style sets the composition, the prompt describes the scene, the saved face carries the expression, and the cards decide the surface.

GoalSubject lookText effectBackgroundHook
A verdict faceExtreme Close-UpFat 3DDark StudioNone
Gaming energySpeed BlurNeon GlitchSpeed LinesNone
A money storyStudio PortraitGoldPoor vs RichCash Burst
A versusSticker Cut-OutSticker OutlineSplit ContrastVS Badge
A warning3D Pop-OutFat 3DDark StudioWarning Tape
A mysteryNoneIceBokehShadow Figure
A calm lessonStudio PortraitNoneNoneNone

The gaming row is the finish behind the Neon Glitch style and where it misfires, and the money row runs on the doubt-over-shock rule from finance covers where the number does the talking. The last row is deliberate: a Clean Edu cover with no cards at all is often the odd one out in a row of glowing neighbours.

A short procedure for choosing cards

A six-step flow: scene and style first, find the gap at thumb size, one card for the gap, a second only if it agrees, remove an element for any hook, render and check the letters.
Cards come after the scene and the style, one per gap, and a hook always costs an element.

  1. Write the scene and pick the style first, using the six-part prompt structure. Cards refine a scene; they do not replace one.
  2. Shrink the last render, or imagine it at thumb width, and name the one thing missing: separation, energy, a money signal, a seam.
  3. Add one card for that gap, in the category that owns it.
  4. Add a second card only if it agrees with the first on emotion, light, motion and scale.
  5. If the card is a hook, remove an element: usually the small second line of text or a background prop.
  6. Render, then read every letter of any text effect at full size before anything else.

What to do next

Take your last render and run the five checks against the cards it used. If two of them disagree, drop the one that is not doing the job you named in step two, and render again with Tweak so only the finish changes. Then build your own version of the combinations table: three rows for the three kinds of video your channel makes, with the cards written down, so the finish becomes a decision you made once rather than one you remake every upload.

Thumbnail Bench team

We build an AI thumbnail maker and spend our days looking at what earns clicks in the feed. Thumbnail Bench was created and is run by Tim Schroeder, a YouTube creator of several years; the founder notes are his. Everything here is written by the team, checked against YouTube's own documentation where a claim can be checked, and labelled as observation or opinion where it cannot. About us.

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